His only moving and attacking lines better be "BADDA BOOM" and "BADDA BING".
I mean its cool and all but if they just give us a 750 "Gangster Kench' skin I won't be all that impressed. If its a legendary with a new VO (which is highly unlikely, because Tahm still has the biggest VO in the game as far as I know and Riot would be reluctant to replace it) and effects and such, then I'd be fine.
However, he needs something cooler with more effects IMO - a Dark Star or Blood Moon skin would have been interesting. Personally I was pushin for a Bad Santa Tahm Kench last Snowdown. This would have been better as a launch skin. Take my upvote, though, anything for the Kench.
They should do a whole thematic skin theme with the mafia/ gangster theme. I mean like how they did with the project skins, not just one individual skin at a time.